Our reporter Yong Li and intern Shan Qianlan

　　Technology Winter Olympics

　　Light up the cigarette and wind up. In the wind tunnel of the Structural Laboratory of Chongqing University, in front of the alpine ski track model, you can clearly see the smoke drifting chaotically with the wind. This is the research site of the wind environment of the snow field.

What use is this for athletes' competition?

As the Winter Olympics is approaching, reporters from Science and Technology Daily walked into Chongqing University to explore the "technical style" behind the alpine skiing project.

　　The alpine skiing project is one of the fastest and most dangerous projects on the snow field, and is known as the "jewel in the crown of the Winter Olympics".

It originated in the European Alps, also called Alpine skiing. It was gradually formed on the basis of cross-country skiing. Since 1936, it has been listed as a Winter Olympics competition.

In this competition, athletes use potential energy to slide from the top of the mountain to the end of the mountain, and the winner is the one who takes less time.

　　In the upcoming Beijing Winter Olympics, there will be alpine ski downhill competitions.

However, due to our country's climate, ski equipment and venues, this sport emerged relatively late in our country, and its development speed is not fast.

The special project of "Science and Technology Winter Olympics" participated by Chongqing University is aimed at studying the wind environment of snow fields, and provides decision-making basis and support for Chinese athletes and coaches.

　　Through field surveys and 3D modeling, members of the "Science and Technology Winter Olympics" team members of Chongqing University and Associate Professor Yan Bowen from the School of Civil Engineering established a practical, efficient and accurate downhill model for alpine skiers.

　　"Our team went to the Winter Olympics venue four times before and after. Through reasonable simplification of the national alpine skiing center track in the Yanqing competition area, a real track model was established and integrated into the previously established straight road + curve mountain. Downhill sports model." said Li Ke, a member of the "Technology Winter Olympics" team of Chongqing University. At the same time, combined with the numerical simulation results of the track wind field and limited measured data, considering the influence of the environmental wind in different directions on the stadium, the downhill skiing was established. The environment model of, has created a more comprehensive and effective alpine ski downhill model.

　　The wind tunnel laboratory of Chongqing University used to conduct experiments on buildings, bridges and other fixed large-scale buildings, and it was the first time to conduct experiments on athletes.

　　It is understood that the factors affecting athletes’ sliding include the athlete’s body shape, technical tactics, track conditions, snow conditions, wind speed, and characteristics of ski equipment. During the sliding process, athletes are subjected to gravity, air lift and resistance, ground support and friction, as well as The role of skeletal muscle strength, among which air resistance has a great relationship with the athlete's posture.

From the monitoring data, the wind speed of the competition field can reach more than 20-30 meters per second, so the direction of the environmental wind speed of the competition field will also have a great impact on the athletes' sliding.

　　"The first part of our work is to study the wind environment, of which about 70% of the content is completed by computer. First, the computer simulates the wind environment of the entire earth, and then simulates the wind environment of a specific area to collect data for subsequent research." Li Ke introduce.

　　In addition, it is necessary to study the relationship from wind to force.

"Knowing the force can understand the movement, and if you want to know the force, you have to perform mathematical modeling. We need to build an athlete's downhill model to study how the athlete receives the force when he adopts different postures, and what is the wind load situation. "Li Ke introduced that this research will assist coaches in formulating a personalized scientific training program that integrates tactics, equipment and physical fitness for each athlete to improve competition performance.

"They sincerely hope that the members of the national team can achieve good results in the game!"